Propagation of nerve impulses & Factors that affect the speed of propagation Flashcards
from trigger zone to axon terminal
propagation aka conduction or distance traveled
What are 2 other names for propagation?
conduction
distance traveled
What occurs with unmyelinated axons?
continuous conduction
the nerve impulse flows from one part of the membrane of the axon to the next
continuous conduction
What is special about continuous conduction?
it iccurs with unmyelinated axons
This is much faster than continuous conduction?
saltatory conduction
myelination insulates the axon resulting in action potentials occuring only at the myelin sheath gaps (nodes of ranvier)
saltatory conduction
the action potential “leap frogs”
saltatory conduction
What are the 2 factors taht affect the speed of propagation?
presence of myelin sheath
diameter of the fiber (axon), the larger the diameter the faster the speed
Nmae the group of fibers from largest to smallest.
group A
group B
group C
Name the group of fibers from fastest to slowest.
group A
group B
group C
What is the myelination for the 3 groups of fibers?
group A = thick myelination
group B = slightly myelinated
group C = unmyelinated
Where are group A fibers located?
somatic nervous system both sensory and motor neurons serving the skin, skeletal muscles and joints
Where are group B fibers located?
autonomic nervous system function in transmitting info from the internal organs to the brain and spinal cord
Where are group C fibers located?
same as B fibers only slower to transmit
